1. Toyota has been working on hydrogen-powered cars the longest, having put 23 years into the technology. Here we see its hydrogen car, the Toyota Mirai.

Toyota

The automaker has been selling the Toyota Mirai in Japan since December 2014, but began sales in California in October 2015 — marking the first time hydrogen-powered vehicles were sold in the United States.

5. BMW is working on a hydrogen car starting in 2020.

BMW says its hydrogen car will have a range exceeding 300 miles and a refuel time of under five minutes.

BMW

6. Ford is aiming to launch the first affordable, mass-market vehicle by 2017.

Ford

In January 2013, Ford announced it was teaming up with Mercedes-Benz's parent company Daimler and Nissan to accelerate the creation of fuel cell technology. There's no word yet on how the car will perform.

7. Mercedes-Benz is making a plug-in hydrogen car called the GLC F-Cell. The automaker says it will have an all-electric range of 30 miles, and a collective range of 310 miles with the hydrogen fuel cell.

Mercedes-Benz

The hydrogen tank can be refilled in just three minutes. The car will be released in 2017, but there's no word on price yet.